On Wed, Oct 21, 2015 at 01:12:01AM +0200, Rafael J. Wysocki wrote: > Well, we already have that in the MFD case, but in principle it may be > problematic for things like power management (say you want to put a > child device into D3, so you use _PS3 on its ACPI companion and then > the parent is powere down instead). That case I understand and we should not allow that. However, here we have an I2C adapter which is purely Linux abstraction that does not have any representation either in DT nor ACPI. And we don't do any power management for that either. If I understand correctly, DT shares the same of_node for both the host controller device and the adapter which then makes it possible to enumerate devices behind by just looking adap->dev.of_node. In case of ACPI we need to know that it's the parent device that we should look for child devices which may not be true always (like what this patch is trying to resolve). > At least, devices in that setup should not be attached to the ACPI PM > domain. Agreed. Currently acpi_dev_pm_attach() only attaches the first physical device to the ACPI power domain so this should be taken care already. -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
